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Gear / Technical Help => Microphones & Setup => Topic started by: §†∑∫åµÞ≥¥ on February 24, 2005, 07:58:05 PM
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... other than the price, of course. Any SPL differences? I have Sound Pro AT933's (853 caps). Thanks...
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Yes my understanding is there is a difference.......
Without the battery box the mics have a spl of around 110 and the dynamic range is 83
with the batterybox the spl is 125 and the dynamic range is 98
with the samson phantom mods it 138 and the dynamic range is 111
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the 8533x is just AT's phantom power module. Not sure of any SPL differences, but the AT does have a low freq rolloff, "150 Hz, 6 db per octave"
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no difference
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there just voltage reducers 48V > 18V nothing more nothing less.
Brad
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there just voltage reducers 48V > 18V nothing more nothing less.
Brad
brad;
they are a bit more than that. the input is unbalanced (signal, supply voltage, ground) and the output is a transformer balanced output.
marc
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They also take the voltage down to about 7-8V, not 18V. The SP bat box and the AT box do about 5-6V. Marc, can you confirm this with absolute numbers?
I think the AT are a tad bit shorter than the Samsons, that's just by eye tho.....
ANDY
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The Samson's also have belt clips.
My basic question is: will I notice a difference in sound between the two if I use a preamp? Anyone?
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i am very curious also if these two modules sound the same when used with a pre-amp, specifically the ua-5.
marc, is there a specific reason why you chose the AT modules over the Samson ones when building your active nak setup?
i got some great help from ATUSA's techy about voltages, etc. i asked the Samson's tech the same questions about the PM4 and got nowhere really slow.
marc
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so if you don't know if there is a difference probly no one will.
the reason i ask is b/c busman2 has a pair of naks for sale that he modded with the samson modules on the end. i was thinking about snagging them, but don't know if they are comparable to your mod.
here is a pdf w/ info on the samson's
http://www.samsontech.com/products/relatedDocs/qe_qv_pm4_manual.pdf
i'm sure jklabs would be answer the question better than i can.
PM4 (For use with QE/QV Headset Mics)
Frequency Response (+-0, 1.5dB): 20Hz—20kHz
Connectors
Input: TA3M Switchcraft
Output: XLR Male (gold plated)
Operating Voltage: 12 Vdc through 48 Vdc
Impedance (@ 1kHz nominal)
Input: 2kΩ
Output: 600Ω balanced (transformer coupled)
Input Wiring
Pin 1: GND
Pin 2 Audio
Pin 3: + Phantom
Output Wiring
Pin 1: GND
Pin 2 Hot +
Pin 3: Cold –
Casing: Zinc, die cast
the input is the same as the AT8533(x) adaptors. i've seen that .pdf before and had it open when i spoke to the Samson tech. he couldn't (or wouldn't) tell me what the supply voltage was on pin 3 of input. he kept telling me that the input was a balanced connection........wrong!!
marc
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so if you don't know if there is a difference probly no one will.
the reason i ask is b/c busman2 has a pair of naks for sale that he modded with the samson modules on the end. i was thinking about snagging them, but don't know if they are comparable to your mod.
here is a pdf w/ info on the samson's
http://www.samsontech.com/products/relatedDocs/qe_qv_pm4_manual.pdf
i'm sure jklabs would be answer the question better than i can.
[snip]
the input is the same as the AT8533(x) adaptors. i've seen that .pdf before and had it open when i spoke to the Samson tech. he couldn't (or wouldn't) tell me what the supply voltage was on pin 3 of input. he kept telling me that the input was a balanced connection........wrong!!
marc
Hi there.
I know the PM-4 well. As in very well. I do not know the AT units at all.
These units do a lot more than just drop the voltage. They draw power from P48. From that they create a powered interface that the mics work into. The mic signal is extracted (in the case of the PM-4 wo loading the mic at all), buffered and sent out on the XLRs.
Whoever designed the circuitry used in the PM-4 was clever: a few parts doing a very complex task. Yes I too wonder about the transformer but probably it was more important to output a true balanced signal (to drive long cables with high rejection of hum etc) than direct coupling provides.
What I'm less happy with is the parts that go into the PM-4 and their orientation.
So to me the question of which power unit is the best is still open. Well on a second though maybe I know but of the ones mentioned I mean :-)
Blu666z has a pair of modded PM-4 if anyone at some point has the time and energy to do a full test of PM and AT power units.
Jon